DEXA Scan Results: Osteoporosis

Clinical Scenario

Barbara Collins, 72, a retired teacher, attends to discuss her DEXA scan results following a Colles fracture from a standing-height fall 6 weeks ago. The DEXA shows a T-score of -2.8 at the hip and -3.1 at the lumbar spine, confirming osteoporosis. She has been on long-term prednisolone 5mg daily for polymyalgia rheumatica for 3 years. She is not on any bone protection. She is anxious about the diagnosis and worried about further fractures, particularly a hip fracture. She wants to know what osteoporosis means and what she can do about it.

What This Case Tests

Explaining DEXA scan results and T-scores in accessible language; presenting a comprehensive osteoporosis treatment plan including bisphosphonates; identifying steroid use as a major modifiable risk factor; discussing falls prevention strategies; explaining the difference between osteoporosis and osteoarthritis; addressing fracture anxiety with practical risk reduction strategies

Common Mistakes Trainees Make

The three most common mistakes are: explaining T-scores using statistical language that means nothing to the patient — 'your bone density is 2.8 standard deviations below the mean' is incomprehensible to most people; prescribing a bisphosphonate without addressing the steroid use that is driving the bone loss — she should have been on bone protection from the start of long-term prednisolone; and failing to address falls prevention, which is equally important as pharmacological treatment in reducing fracture risk in elderly patients.

The Consultation Challenge

Barbara is anxious. A wrist fracture from a simple fall has been followed by a diagnosis that implies fragile bones. She is worried about hip fractures and loss of independence. You need to explain clearly, treat comprehensively, and address her fears.

Explain the DEXA results in plain language: 'Barbara, the DEXA scan measures the density of your bones — essentially how strong they are. Your results show that your bones are thinner than they should be for your age. We call this osteoporosis, which literally means porous bones. Your scores of -2.8 and -3.1 confirm that you are in the osteoporosis range, which means you have a higher risk of fractures than average. The wrist fracture from a standing fall was likely a consequence of this.'

Address the steroid connection: 'One of the main reasons your bones have thinned is the prednisolone you have been taking for your polymyalgia. Steroids are very effective for the condition they are treating, but they have a significant impact on bone strength over time. This is something we should have protected against from the start, and I am sorry that bone protection was not started alongside the prednisolone. We are going to address that now.'

Present the treatment plan: start alendronate 70mg once weekly (or risedronate if preferred) — explain the specific taking instructions (first thing in the morning, empty stomach, with a full glass of water, stay upright for 30 minutes). Prescribe calcium and vitamin D supplementation (Adcal-D3). Check her vitamin D level if not recently done. Discuss whether the prednisolone dose can be reduced in consultation with rheumatology.

Address falls prevention — this is as important as medication: assess her home environment (loose rugs, poor lighting, bathroom rails), review her medications for anything that increases fall risk (antihypertensives causing postural hypotension, sedatives), discuss footwear, and consider referral to a falls prevention programme or physiotherapy for balance and strength training.

Reassure about hip fracture anxiety: 'I understand your worry about a hip fracture. The good news is that we are catching this and treating it now. With the right medication, your bone density will stabilise and may even improve. Combined with falls prevention, we can significantly reduce your fracture risk. You are not powerless in this — there is a lot we can do.'

Time check: Minutes 1-3 on explaining DEXA results in accessible language. Minutes 3-6 on the steroid connection and bisphosphonate treatment plan. Minutes 6-9 on calcium and vitamin D, falls prevention, and home assessment. Final 3 minutes on reassurance, follow-up DEXA timing, and addressing anxiety.

How Examiners Mark This Case

Data Gathering and Diagnosis: Examiners assess whether you explain the DEXA T-scores in accessible language, identify the steroid use as the primary modifiable risk factor, and assess other contributing factors — diet, exercise, smoking, alcohol, family history, early menopause. Checking vitamin D status and medication review for fall-risk drugs demonstrates thoroughness.

Clinical Management and Medical Complexity: Examiners evaluate whether you prescribe an appropriate bisphosphonate with correct administration instructions, add calcium and vitamin D supplementation, address falls prevention comprehensively, and discuss the steroid dose with a view to reduction. Knowing the follow-up DEXA timing (typically 2-3 years after starting treatment) shows management continuity.

Relating to Others: Examiners look for empathetic communication about a diagnosis that implies fragility, honest acknowledgement that bone protection should have been started earlier, and practical reassurance that treatment is effective. Addressing her hip fracture anxiety with concrete risk reduction strategies empowers rather than frightens her.

Example Opening

Strong opening: "Hello Barbara, I have your DEXA scan results here. Before I go through them, how has the wrist been healing? And how have you been feeling about things since the fracture?"

When explaining the results: "The scan shows that your bones are thinner than we would like — a condition called osteoporosis. Think of it like a honeycomb structure where the holes have got bigger and the walls thinner. This means the bones are more likely to fracture from a relatively minor injury, which is what happened with your wrist. But the important thing is that we now know about it, and there are very effective treatments."

Avoid: "Your T-score is minus 3.1, which is 3.1 standard deviations below the young adult mean" — this is statistically accurate but clinically useless for patient communication.

How This Appears in the SCA

Explaining DEXA results tests your ability to translate complex diagnostic information into patient-friendly language, manage a treatment plan that includes both pharmacological and non-pharmacological elements, and address the iatrogenic contribution of steroid use honestly. Examiners value a comprehensive approach that combines bone protection with falls prevention.

Key Statistic

Long-term glucocorticoid use increases fracture risk by 50-100%. Approximately 30-50% of patients on long-term steroids will develop osteoporotic fractures, yet bone protection is prescribed in fewer than half of eligible patients.

Relevant Guidelines

• NICE CG146: Osteoporosis — assessing the risk of fragility fracture
• NICE TA161: Alendronate, etidronate, risedronate for secondary prevention
• NICE CG161: Falls in older people
• NOGG guidance on glucocorticoid-induced osteoporosis.

Frequently Asked Questions

How do I explain T-scores to a patient without using statistics?

Use a visual analogy: 'Think of bone like a honeycomb. Healthy bone has small holes and thick walls, making it strong. In osteoporosis, the holes get bigger and the walls get thinner, making the bone more fragile. The DEXA scan gives us a score that measures this — your score tells me your bones are significantly thinner than normal, which is why we call it osteoporosis.' Avoid standard deviations, means, and z-scores — these are meaningful to clinicians but not to patients.

How should a patient take alendronate correctly?

The instructions are specific and important for both absorption and safety: take first thing in the morning on an empty stomach, swallow whole with a full glass of plain tap water (not tea, coffee, juice, or mineral water), remain upright (sitting or standing) for at least 30 minutes after taking it, do not eat, drink anything other than water, or take other medications for 30 minutes. These instructions prevent oesophageal irritation and ensure absorption. Many patients stop bisphosphonates due to GI side effects that are actually caused by incorrect administration.

Why should bone protection be started with long-term steroids?

Glucocorticoids cause bone loss from the first month of use by suppressing osteoblast function (bone formation), increasing osteoclast activity (bone resorption), reducing calcium absorption, and decreasing sex hormone production. NOGG and NICE guidelines recommend assessing fracture risk in anyone starting glucocorticoids expected to last 3 months or more, and starting bone protection (bisphosphonate plus calcium and vitamin D) in those at increased risk. Barbara should have been started on alendronate when the prednisolone was initiated. This is a common prescribing omission.

What falls prevention measures should I recommend?

Home assessment: remove loose rugs, ensure adequate lighting especially on stairs and at night, install grab rails in the bathroom, secure trailing cables. Medication review: check for postural hypotension from antihypertensives, sedation from antihistamines or benzodiazepines, and dizziness from any cause. Footwear: well-fitting, supportive shoes with non-slip soles. Exercise: strength and balance training — tai chi, physiotherapy-led balance classes, or community falls prevention programmes. Vision: ensure an up-to-date eye test. These non-pharmacological measures are as important as bisphosphonates in reducing fracture risk.

When should a follow-up DEXA scan be arranged?

Repeat DEXA scanning is typically performed 2-3 years after starting bisphosphonate treatment to assess response. An earlier scan is not useful because bone density changes take time to become measurable. If the T-score has stabilised or improved, continue treatment. If bone loss is continuing despite treatment, reassess adherence, consider alternative bisphosphonate or second-line treatment (denosumab, teriparatide), and check for secondary causes of osteoporosis. After 5 years of bisphosphonate treatment, a drug holiday should be considered in lower-risk patients.